The present invention relates to a print head for an ink-jet printing apparatus which ejects ink droplets onto a sheet of paper for recording.
A conventional print head is disclosed in the Hewlett-Packard Journal, May issue, 1985, Vol. 36, No. 5, particularly on pp. 21-26 and pp. 33-37. In the print head, a heater is provided in an ink chamber, and the vapor pressure produced by the heater enables ink droplets to be ejected toward a sheet of paper. The conventional print head comprises a plurality of heater elements formed on a substrate and a nozzle plate covering the substrate. A plurality of barrier walls are provided on the nozzle plate in order to provide an ink chamber for each of the heater elements. The nozzle plate is provided with nozzle holes at positions between the barrier walls in alternate arrangement to form a multi-nozzle print head.
In the conventional print head, it is extremely difficult to precisely align the barrier walls and the nozzle holes of the nozzle plate with respect to the heater elements formed on the substrate. As a result, the contents of the ink chambers are not constant to deteriorate the uniformity of ink-injection characteristics of the ink chambers.